We may overrun the bounds because linfo and jited_linfo are already advanced to prog->aux->linfo_idx, hence we must only iterate the remaining elements until we reach prog->aux->nr_linfo. Adjust the nr_linfo calculation to fix this. Reported in [0]. [0]: https://lore.kernel.org/bpf/f3527af3b0620ce36e299e97e7532d2555018de2.camel@xxxxxxxxx Reported-by: Eduard Zingerman <eddyz87@xxxxxxxxx> Fixes: 0e521efaf363 ("bpf: Add function to extract program source info") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> --- kernel/bpf/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index fe8a53f3c5bc..61613785bdd0 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -3244,6 +3244,7 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char * struct bpf_line_info *linfo; void **jited_linfo; struct btf *btf; + int nr_linfo; btf = prog->aux->btf; linfo = prog->aux->linfo; @@ -3258,8 +3259,9 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char * insn_start = linfo[0].insn_off; insn_end = insn_start + len; + nr_linfo = prog->aux->nr_linfo - prog->aux->linfo_idx; - for (int i = 0; i < prog->aux->nr_linfo && + for (int i = 0; i < nr_linfo && linfo[i].insn_off >= insn_start && linfo[i].insn_off < insn_end; i++) { if (jited_linfo[i] >= (void *)ip) break; -- 2.47.1
